1. Field of the Invention
The present invention relates to: a transfer position teaching method of teaching a hand for transferring a substrate to a substrate transfer member a transfer position of the substrate; a transfer position teaching apparatus for teaching a transfer position of a substrate; and a substrate processing apparatus having a hand for which teaching of a transferring position is made by the transfer position teaching apparatus or the transfer position teaching apparatus.
2. Description of Related Art
There are cases where substrates such as glass substrates for organic light emitting displays, glass substrates for liquid crystal displays, panel displays for solar cells, glass substrates for plasma displays, glass substrates for photo masks, substrates for optical disks, substrates for semiconductor wafers are supplied in a stacked condition in a substrate-storing container in a substrate processing apparatus. For example, in a substrate processing apparatus processing semiconductor wafers, semiconductor wafers are carried into the substrate processing apparatus being stored in a container so called FOUP (Front Opening Unified Pod) and carried out of the substrate processing apparatus. Herein “FOUP” refers to a hermetically closed-type storing pod for semiconductor wafers in conformity with SEMI (Semiconductor Equipment and Materials Institute) standards.
In order to precisely execute a transfer of a substrate between a substrate-storing container as such and a hand as a transfer mechanism for substrates, it is required that accuracy of transfer of substrates by the hand be improved. For this reason, it is required to execute a teaching process of transfer positions called “teaching” in order to identify and store transfer positions of substrates by the hand.
Conventionally, in order to conduct teaching of transfer positions of semiconductor wafer, teachings are conducted by setting a dummy semiconductor wafer on a hand and then visually recognizing positional relationship between the semiconductor wafer and FOUP or jig comparable to FOUP.
International publication 2010/004635 describes a teaching method for robots in which a wafer is caused to contact an inner wall face of a cassette to detect a point at which angular change of servo motor begins based from positional changes for an encoder, thereby detecting posture of the robot arm and angular position of shaft at the time.
In cases that a teaching of a transfer position of a semiconductor wafer, it is required to operate a hand while visually recognizing a gap between the semiconductor wafer on the hand and a FOUP. For this reason, it is difficult to recognize the positional relationship between the semiconductor wafer and the FOUP. Also, output may be uneven among operators. Therefore, it is difficult to accurately teach transfer positions of semiconductor wafer.
Also, in order to conduct a teaching of transfer positions of a wafer by detecting a contact between the wafer and a cassette with a robot for transferring wafers as described in international publication 2010/004635, it is required that the robot is provided with such detection mechanism. Thus it is not possible to conduct this type of teaching on existing substrate processing apparatuses.